You're right on with driving in reverse:
Teardrop aerodynamics... in reverse!
With your hatch sloped like that there is a lot of room for a Kammback. My roof extension + rear wheel skirts reduced fuel consumption by 8% at 100km/h (60mph). Your Kammy could be longer than mine, reducing the turbulent wake even more. Have a look at
my modding thread for details.
Brucey is right: It's easiest to start with a grille block.
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e·co·mod·ding: the art of turning vehicles into what they should be
What matters is
where you're going, not
how fast.
"... we humans tend to screw up everything that's good enough as it is...or everything that we're attracted to, we love to go and defile it." - Chris Cornell
[Old] Piwoslaw's Peugeot 307sw modding thread